Evaporating appratus.



L. P. BAUER.

EVAPORATING APPARATUS.

APPLICATION FILED APR. 29. I9II.

PalentedJune 22, 1915.

2 SHEETS-SHEET 1.

L. P. BAUER.

EVAPORATING APPARATUS.

LJi AJWABQ APPLICATION FILED APR.29,I9I1.

Patented June 22,1915.

2 SHEETSSHEET 2.

LOUIS 3P. BAUER, 0F JPN,- ILLINOIS.

EVAJPOTING APPARATUS.

masses.

Specification of Letters Patent.

Patented. June 22, NW5.

Application filedApztlctB; 2 .911. Serial'llto. 624 M.

To all whom it may concern:

Be it known that 1, Louis =P. Bapnma citizen of the UnitedStates,.res1d1ng.at

Pekin, in the county of Tazewe'll and State.-.

evaporators and particularly to vacuum e vaporators- It pertainsprimarily to a structure in an apparatus for evaporatingliquids ofvarious kinds by which a very high efiiciency may be maintained at alltimes.

Many evaporating pans are so equipped that the heat necessary. forevaporation cannot be applied to a suflicientdegree to obtain thequickest and best results... Furthermore, a high efliciency of thesepans cannot be maintained since the interior structures are such thatthey soon become clogged and covered with incrustations, the heatingsurfaces after a short time-being rendered less and less useful by suchincrustations, and in order to restore efficiency the surfaces must, ofcourse, be cleaned requiring the apparatus to be ,shut down. Whencleaned the apparatus may stand at say 100% efliciency in heattransmission, but later this gradually falls to a very low point,because the steam introduced thereto cannot yield the best results byreason of the adhering matter.

Havingthis in mind one ofmy objects is to produce an interiorstructurefor a vacuum pan in which the entire heating surface can alwaysbe utilized to the best advantage. That is to say, anobject is toprovide such an arrangement in anevaporatingapparatus that its parts canbe maintained practically free of: adhering matter so that itsefliciency will be maintained at practically 100%, or an efliciencyafter long use which will substantially equalthat at which it stood atthe beginning:

Another object is to provide a structure in a vacuum. pan-in which-theheating elementor eiementsiare'made to evaporate the liquids undertreatment either by immersion of said element in the liquid orby treatmgsaid. liquor through the well known film process of evaporation thesemethods being elective, the latter, however, being preferred;

Another object is to provide a vacuum panuin which the largest heatingsurface that .it is possible to produce in a pan, can always bemaintained.-

Another and important object is the provision of an evaporatingapparatus yielding rapid results-in the evaporating process. A furtherobject-is the accessibility to all the parts of an evaporating apparatusby providing for the withdrawal of its heating and evaporating elementfrom the pan for making repairs.

A further .objectis to provide a vacuum pan-with-an open side throughwhich the mechanism that assists in the 'process of evaporation canbe'introduced or removed, such open side being provided, of course, witha tight closure.

A further object is to provide an evaporating mechanism for a vacuum pancomposed of-a' number of parts built up to constitute a complete heatingunit, all said parts being. clamped together for immersion inthe'liq'uid to be'evaporated.

A further object is to provide, in a vacuum pan, a mechanism for thereception of the heating member and to provide means for automaticallykeeping the said-member cleared of deposits by revolving one of theparts relatively to the other.

Other objects and advantages will appear in the following specificationaided by the accompanying drawings in which,

Figure 1 is a rearelevation of a vacuum pan. Fig. 2 is a verticallongitudinal section of the casing of the vacuum pan. Fig. 3 is asectional elevation of the lower half of the same-0n a much enlargedscale. Fig. 4 is a rear elevation of the lower half of the'pan, also onan enlarged scale. Fig. 5 is an elevation of a heating element, andFig.6 is a longitudinal section of certain parts shown in Fig. 3 on agreatly enlarged scale.

From wide experience with various types of' evaporators it has beenfound that although any one of them may operate satisfactorily and witha high efliciency under certain definite conditions, it may failentirely to give satisfaction under other conditions. For example, itmay be well suited to the demands of sugar plants but when called uponto evaporate distillery slop, tankage, or steepwater in starch andglucose plants, or, in general, liquid which tends to form voluminousand slimy precipitates during concentration, the evaporator may be acomplete failure. From this knowledge I have been able to construct avacuum pan having a heating element that can be kept clean duringoperation so as to maintain the desired high efliciency and to soarrange the structure of the entire apparatus that this element may bereadily and quickly removed from the pan in case of needed repairs.

Those familiar with evaporator-s realize the serious delays causedby'leaks in the ,heating system, the adhering of scale andincrustations, the necessity of boring out plugged vents and thenumerous other sources of trouble all of which the structure to bedescribed herein is designed to eliminate.

I prefer in my vacuum apparatus when using the socalled pan indicated asa whole by the letter A, to make it in two sec tions for convenience,there being an upper and a lower one indicated by a and b respectivelyand joined in any usual manner as, for instance, by means of flangesindicated' at 0; At the top of the upper section is a flanged outlet,connection 03 for a vapor pipe not shown, while the lower section atthe bottom is provided with a similar flanged connection 6. What I termthe rear side of the pan, for convenience, is provided with an opening Bhaving a plate 0 as a closure therefor. This said plate is provided witha central opening D to'receive certain rotating portions, to behereinafter described, while the front side of the pan has a' similarbut larger opening E. The

heating member or unit for evaporating purposes is made up of a seriesof hollow disks F indicated clearly in Figs. 3 and 6. The latter figureshows these disks on quite a large scale as compared with Fig. 3, mostof the said disks being shown in transverse section. They are eachcomposed of two dishedplates f provided each with a circumferentialflange g placed upon one another, as indicated, forming a receptacle forsteam. The disks thus made up are clamped together near their centerswith rings or gaskets G between them, there also being within each diskbetween the plates f a gasketor ring I-I. When all the disks and saidrings are secured together as, for instance, by means of bolts J, aconduit K is created through the entire series of disks or throughoutthe entire length of the unit. It is understood, of course, that thecenter portions of all the disks are removed leaving openings ofsubstantially the same diameter as the bores of the said rings all ofthe latter serving to make close joints so that there can be, no leakageof fluids, using red-lead or similar material if desired to makeanabsolutely tight joint. \Vhen thus assembled a bore L is also createdwhich extends through all of the rings and the disks F as shown bypreviously having provided holes in all of these parts to be broughtinto register. Communicating with said bore L within each disk is a pipeM secured in each of the rings H by means, for instance, of screwthreads M, the opposite open end of each said pipe terminating adjacentto the inner wall of the disk at the flanged portion of the same. Ineach said ring H, also, are two openings M permitting communicationbetween the bore K and the interior of each disk. Against each end ofthe unit made up of the series of disks is a plate. One is indicated atN, and the other at N the said bore L being closed by the said plate N,and these plates serve as the actual clamping members through said boltsJ. The plate N is provided with a bore 0 which communicates with and isperpendicular to the said bore L, while a centrally disposed bore P insaid plate communicates with said bore 0 and lies parallel to the saidbore L, said plate having a central extension Q, wherein said bore P iscentrally disposed with reference to the circumference of the disks andthis extension Q lies within the bore D of the plate 0, there being anyusual stufling-box R to prevent leakage around said extension.Communicating with the bore P is a pipe S, there being a packing glandat T also to prevent leakage around said pipe.

The opposite plate N is provided with a bore U communicating with theinterior bore K of the disks and rings and upon this is placed theflange V of a hollow stem or pipe V which flange may be secured to saidplate N by means of a series of bolts but two of them being shown,however, at V in Fig. 3. The stud-bolts thus provided serve to clamp thesaid stem or pipe and the plate N rigidly together, any means (notshown) being used to provide for a fluid tight joint between them. Thesaid stem or pipe V extends through the bore E of the front of the panand a suitable stuflingbox W provides for maintaining a'tight joint.Secured to said stem or pipe in suitable manner is a worm wheel 2 whichmeshes with a worm 3 mounted on a shaft l supaaaaraa said pipe or stem Vit being understood,

however, that any other means of rotation may be used. A flange 6 on theouter end of the pipe provides for the attachment of any suitable steamconnection (not shown) all of which, however, will be understood later.

ln the device illustrated I prefer to rotate the series of disks whichare partially immersed in the liquor intended to be evaporated and, asstated, this is done through the worm and worm-'wheel'and although theextension Q and sterner pipe VT may constitute shafts to support thedisks in the bores D and B other ways'of supporting the disks may beused. I prefer-to mount the unit between spiders 7 for convenience inremoving the mechanism from the pan in the easiest possible way. Eachspider is provided with a body of sutlicient area,

Fig. 4, to be bored out at 8 to receive the plates N, N and each has,also, a series of arms, two opposite ones 9 of which are connected bybars 10 to move on runways 11 shown in said Fig. 4 and indicated bydotted lines in Fig. 8. Preferably it provide a series of balls 11 forthe runway to support these bars and for providing for easy movement ofsaid bars in removing the mechanism for the pan. The spiders furtherinclude two arms 12 disposed at right angles to the said arms 9. As amatter of fact their exact position relative to the arms 9 is notimportant, that described being merely a preference. Connecting theopposite arms 12 of each of the spiders'is a bar 13, Figs. 3

and 4, which serve to space said spiders apart and secure themrigidlytogether.

The'numeral 14 indicates a series of chains :whose ends are secured tothe members 13 in suitable manner, each chain having a position betweentwo adjacent 'disks F as clearly shownin Figs. 3 and 6 although in thesefigures they have not been shown in full in order to leave the drawingclear and easily read. In Fig. 4:, also, the position of one of thechains is shown wherein at its middle it lies against .one of the ringsH, its extremities lying upon the full exposed surface of each diskoutward from said rings.

It is now to be noted that since the disks are adapted toorevolveindependently of the spider and thechains 14: the -are continuallyrubbed o'r sdrap'ed by sai' chains resulting in keeping those surfacesentirely free of adherin matter and incrustations which naturally orm,each chain being of such a size as to lie snugly between two adjacentdisks so as to insure actual frictional, wiping or rubbing contact withboth. It is to be stated, however, that other means for producing therubbing of the disk surfaces metal surfaces cleaned. It may be statedfurther, however, that the most important ofice' of these chains, ropes,or equivalent members, is'that of keepingthe liquors in a turbulentcondition and in a marked degree preventing incrustations forming uponthe heated disks.

It is evidentthat as the disks revolve the tendency of the liquor is tofollow in the direction of rotation and to be drawn up between the disksduring such rotation. But the chains or other members used lie in thepath of the liquor, resulting in keeping it in agitation upon thedisk-surfaces keeping them free and clean of adhering matter.

The disks in their rotation will naturally cause the liquor to take upmore or less of a whirling motion in the same direction but thechainsbreak up andprevent said whirling motion.

I provide means for introducting steam as the evaporating agent andprovision is also made for the removal of air, gases, and

the water of condensation. In the present instance the steam isintroduced through any pipe connection, not shown, which may be boltedto the flange 6 on the outer end of the rotating stem or pipe V; thencepassing into the central conduit IQ where' it enters the disks F throughthe openings M in the rings H while thepipe S at the opposite end of theapparatus is the discharge for air and gases and condensed steam. Thedisks in rotating and in being partially immersed in the liquorundertreatment are continually covered with a film of'said liquor whichthesteam within quickly evaporates; the vapor passing off through the upperpart of the pan and the connection (Z at the top. Water of condensationformed in the disks will be withdrawn through the pipes M as their openends become immersed therein, due to pressure of steam within the disks,the water being forced up from time to time through said pipes into thebore L, and finally out through the bore P, as the pressure of steam ihere given. The width of the pan measured.

between the closure C and the front end of said pan is in theneighborhood of 30 inches while the thickness of the disks is aboutthree quarters of an inch; there being a space between each. disk offrom one half 15.

inch to five eighths of an inch, and the diameters of said disks are inthe neighborhood or 36 inches. It is thus seen that a very large heatingsurface is providedand in fact a much larger one than would be 'posslbleby. any other form of heating device such assteam coils, for example.Since the spiders remain stationary and have the rating apparatus ofwhich I am aware.

Instead of rotating the series of disks the spiders may be rotated, thesaid disks in "this case effecting the evaporation by their immersiononly. However, to assist in evaporation the chains in rotating with thespider will act to keep the exposed surfaces of the disks covered with afilm of liquor which will aid-materially in the speed of evaporation. I

If atany time it is desired to withdraw the mechanism from the pan forrepairs it is only necessary 'to remove the stud-bolts V These arereadily reached from the front side of the pan by removing a coveringplate V of a hand hole V in said front side, the series of disks beingturned little by littleso as to bring the several said bolts uppermost,one at a time, where each can be reached with a wrench through the saidhole. Having removed these, the closure C at the rear side of the panhaving been removed, the entire inner mechanism can be readilywithdrawn, the flange V being removed from the plate N. After repairsthe mechanism is replaced in the position it first occupied.

Other types of evaporators have used rotating heating elements but noneof them have been arranged upon a supporting track so as to be easilyand quickly withdrawn but must be withdrawn at the expense ofconsiderable hard work and loss of time since theends only thereof aresupported' -within the receptacle in which the element lies. In mypreferred form of element, however, made up of disks which 1t is thedesire to partially submerge, and which 11; 1s also the desire torotate, the structure is such.

that said element almost entirely fills the pan or receptacle and atrack is desirable in order to easily and quickly remove from and returnthe element to the pan. Necessarily, also, a support movable upon thetrack and in which the element can rotate is used as a novelconstruction as differing from evaporators having an element slidablymounted on a track but not adapted to rotate and which thereforerequires no support between it and the track.

The ease and readiness with which the disks F can be built up to make aheating unit by the using of the several dished plates f together withthe described rings or gaskets G H is important since but little fittingof parts is required thus resulting in a saving of time. And furthermorethe unit can be made of any desired extent of heating surface, more orless of the disks being used to suit requirements.

In my apparatus a much larger heating surface is provided than ispossible with any other plan of the closed type working under vacuum andhaving the same interior space, the efficiency of the same is maintainedat the highest point, and both the film method.

of evaporation and the common method of immersion are possible.

I desire to state that it is not my intention to be confined to theexact structure shown in the drawings and described herein since variouschanges may be made that will lie within the meaning and intent of theinven tion. Any suitable means may be used to support the disks whenthey remain stationary and any suitable driving connection may beemployed to impart movement to said chains. When the disks are to remainstationary the pipe M may be duplicated within each disk so that whileone is uppermost, as shown in Fig. 5 for the remoy'al of the air, theother may open into the bottom of the disk for removing the water.

The invention also contemplates the rotation of the disks and chainsrelatively in opposite directions this being possible by certainadaptations of the structures. And beside this the device is susceptibleof other changes.

'lhe area of heating surface of the unit made up of the disks is verylarge compared with the space occupied, and, in fact, it is of anysystem of pipe coils occupying the same space, and the disks being madepreferably of copper have a high heat conductivity. Much stress has beenlaid, 'in practice, upon the advantage of film evaporation and severaltypes of apparatus are based on this method but most of them have notbeen productive of the best results. In the present instance theadvantage of film evaporation is gained and the surfaces of the disksare always kept clean.

The liquor circulates in the narrow spaces between adjacent disks andthis coupled with the high conductivity of the heating surfaces makesthis circulation practically as productive of good results as types ofevaporators of much larger size intended for film evaporation eventhough the said disks larger than it would be possible by the use mayremain stationary, which may be one form of my device as statedpreviously. Furthermore, my form of. evaporator is far more satisfactoryfrom the standpoint of adaptability to the evaporation of all classes ofliquors which is not true of many other types. The speed of rotation andlevel of liquor are under control and can be so reglated as to produceconditions of the very highest efficiency. r

The structure I employ has not. been used in an evaporating apparatusadapted to work under vacuum which is the system by which most allliquors can be handled to the best advantage when considering the matterof time, low cost of the heating agent (spent steam) and ease andrapidity of handling large quantities of liquor.

Having described my claim 1. In an evaporator, the combination of ainvention, I

receptacle and a track therein, of a support mounted upon and adapted tomove along the track and including two spaced end portions, :1 memberhaving hollow trunnions at its ends andcarried byand rotatable in saidend portions, a separate conduit communicating with each said trunnion,and a series of-fiexible members carried by the support and lying inclose proximity to the said rotatable member.

2. In an evaporating apparatus, a receptacle for the liquor to beevaporated, a rotatable member therein comprising a series of hollowdisks separated from one another by a narrow'space, a conduit extendingthrough the disks conducting a heated gas thereto,

and a flexible member lying in each space between adjacent disks, thedisks rotating relative to said members, their surfaces rubbing upon themembers in their rotation.

3. In an evaporating apparatus including a receptacle for liquor to beevaporated, a

track, a rotatable heat containing member in said, receptacle, a memberto carry said rotatable member and mounted upon the track and adaptedfor withdrawal from the receptacle, means adapted for frictionalengagement with the rotatable member, and means for rotating saidmember.

4:. In an'evaporator the combination of a receptacle for the liquor tobe evaporated, a rotatable member therein comprising a series vof hollowdisks each provided with a pair of openings in its walls, supportingtrunnions for said member, rings interposed between the walls of all ofthe disksand con- 'stituting, together with one series of said a vacuumpan, of a series of hollow spaced members rotatably mounted in said pan,means to space apart said members, a'steam conduit directlycommunicating with the members, a discharge conduit for water, a pipe ineach member communicating with said discharge conduit, and a flexiblemember suspended between the adjacent surfaces of adjoining members.

6. In an evaporating apparatus the combination of a pan, a series ofhollow disks, spacing members interposed between the several said disks,a spacing member inclosed in each said disk, means to clamp the seriesof disks and members together, hollow trunnions for carrying the seriesof disks, there bein two separate bores extending through alIthe disksand said members, and a pipe in each disk communicating with one of saidbores. V

'Z. The combination in an evaporating apparatus, of a series of platesadapted in pairs to constitute receptacles for steam, there being twospaced openings in each plate, a ring lying at each side of each plateand provided each with apertures corresponding with those of the platesand together with the latterforming two separate conduits throughout theseries, there being an aperture in each of the rings lying within thereceptacles and each of said apertures communicating with one of theconduits, and a'pipe in each receptacle connected with the other of theconduits.

8. In an evaporating apparatus including a receptacle for the liquor tobe evaporated, a member within said receptacle made up of a series ofhollow disk-like portions, a ring interposed between each pair ofportionsfa ring also interposed between the walls of and within eachsaid disk-like portion, said mit communication of the latter with saidconduit, there being a conduit extending through the rings and the wallsof all the disk-like members, and a pipe within each disk communicatingat one end with the last named conduit. its other end havingcommunication with. the interior of said disk.

9. An evaporator comprising in its construction a series of hollowdisk-like members and a series of rings interposed betweenthem and aseries of rings within them, said members having openings in their wallsto correspond to the openings of the rings, there being an opening also1n each said ring and in each wall of each of the members separate fromthe openings first described, the two separate openings 1n the membersand the rings when all are clamped In testimony whereof I afiix mysignature, 1n presence of two wltnesses.

LOUIS P. BAUER.

Witnesses:

CHARLES V. MILES, EUNICE BECKUM.

